I am generally a fan of semi-automatic exposure systems when looking to photograph wildlife. Specifically, I begin most outings with the camera in Aperture Priority Mode, and having an extra 2/3 stops of lights dialed seems to work pretty often. However, as soon as I see a tricky lighting situation through my viewfinder I will try to get into Manual Exposure Mode as quickly as possible.
Camera settings: 1/200th F/5.6 ISO 200
Above photo is a handheld capture with one of my typical rigs for closeup photography, the Tamron SP 90mm VC lens and the Canon EOS 60D. The goal with this backlit photo was to get a good amount of illumination showing on the butterfly itself. To achieve this, some of the brightest parts of the scene are pushed out of gamut because of the dynamic range restrictions of DSLRs. As cameras are programmed to expose for the median tonal range of an image, it would require a significant increase in exposure compensation to get what I was after. Turning the knob to Manual Mode and dialing in my desired settings was a much more succinct process.
“Blowing out the highlights” is not always a sin in my book, as I’ve learned to “see how a camera sees” and envision the end product. Indeed there is some detail loss on the fringes of the butterfly and also on the petals of the flower, but in this case I think that adds to the “warm” feel of the image.